The official SIG Sauer statement reads:

"SIG SAUER, Inc. is proud to announce the delivery of the 100,000th M17 and M18 for the Modular Handgun System program to the U.S. Military, ahead of schedule, and surpassing the performance standards and requirements since the official contract award in January 2017."
“In the month of October SIG SAUER exceeded our manufacturing requirements by thirty percent and delivered a record-setting 12,100 handguns to the U.S. Military to achieve this historic milestone for SIG SAUER and the MHS program,” began Ron Cohen, President & CEO, SIG SAUER, Inc. “With the strict accuracy and acceptance specifications that the M17 and M18 are continuously exceeding, it’s clear that the success of this program can be directly attributed to the reliability, durability, and accuracy of the handgun, which has resulted in the high demand for both the M17 and M18 from every branch of the U.S. Military.”

Sources: soldiersystems.net, sigsauer.com